It is now common practice in the electrical industry to connect wires to terminals by providing a wire-receiving slot in the terminal, which slot is dimensioned such that when the wire is moved laterally of its axis into the slot, the edges of the slot will penetrate the insulation of the wire and establish contact with the conducting core thereof. It is also common practice to design multi-contact electrical connectors having terminals therein which have wire-receiving slots. A plurality of wires can be electrically connected to a like plurality of terminals in a connector by means of insertion tools which simultaneously insert the plurality of wires into the terminals. Terminals and connectors of these types permit the achievement of substantial cost reductions in the manufacture of electrical harnesses and cables having connectors on their ends and are coming into widespread use for this reason.
It is desirable to provide a strain relief of some sort between a wire and terminal to which the wire is connected so that when a tensile pull is applied to the wire, the load will be transmitted through the strain relief device to the terminal rather than through the electrical connection of the terminal to the wire. A strain relief thus functions as a stress bypass for tensile stresses applied to the wire and protects the electrical connection against damage.
Terminals and multi-contact electrical connectors having wire-in-slot connecting means for connecting the wire to the terminal, have in the past, been provided with several different types of strain relief devices and while these known strain relief devices are adequate under many circumstances, there is a need for an improved strain relief in connectors and terminals of the wire-in-slot type. For example, it is common to provide a terminal having two plate-like sections, each of which has a wire-receiving slot therein. One of these slots each serves to establish electrical contact with the wire and the other slot is dimensioned such that it serves as a strain relief. It is also common practice to provide a strain relief on the housing of a connector containing wire-in-slot type terminals so that tensile forces applied to the wire are transmitted to the connector housing rather than to the electrical connection between the wire and the terminal.
The present invention is directed to the achievement of an improved strain relief which will surpass the performance of previously known strain relief devices on wire-in-slot connecting devices, which does not require strain relief means on the insulating housing containing the terminals, and which can, in general, be used under virtually any circumstances where wire-in-slot type terminals are used.
A preferred embodiment of the present invention comprises an insulating housing having a plurality of side-by-side cavities therein, each of which contains an electrical contact terminal. Each terminal has a wire-receiving portion intermediate its ends and has a crimped portion proximate to the rearward end of the housing. The crimped portion comprises spaced-apart ears which extend from a web and which are offset with respect to each other. The sidewalls of the cavities are cut away in the vicinity of the upper end of each ear so that the ears can be engaged by a crimping tool and bent downwardly towards the web until they are in embracing relationship with the wire. The crimpable portion of each terminal is, moreover, located with reference to the wire-receiving portion, such that a wire can be inserted into a terminal and the crimpable portion can be crimped onto the wire during the single downward stroke of a crimping and inserting tool. Advantageously, all of the wires which are to be connected to the terminals in a connector are inserted into the terminals and the terminals are crimped onto the wires in a one-step insertion and crimping process.